Four teenagers have been convicted of hurling stones through a taxi window − and leaving a 70-year-old passenger with a fractured skull.

Shocking CCTV footage from inside the taxi shows the moment a rock smashes through the window, sending glass shards flying through the cab, and striking the woman on her forehead.

Birmingham Youth Court heard how the young louts − one aged 15, two 16 and a 17-year-old − pelted at least seven black cabs with stones as they travelled along Bristol Road on 25 May last year.

The three younger defendants all denied involvement but were found guilty of causing wounding and conspiracy to cause damage, while the 17-year-old admitted wounding but was found guilty of conspiracy to cause damage. None of the offenders can be named due to their age.

Police have praised the local community for coming forward to help convict the thugs.

Following the attack, local neighbourhood officers and detectives worked with the local community to encourage several key witnesses to come forward.

Birmingham Police Neighbourhood Inspector Steve Rice , said: “This investigation has been a long and involved investigation and I would like to commend the community for having the bravery to stand up to the thugs and to come forward.

“We would like to commend the bravery of the witnesses, who told us they were fed up of a group of youths causing anti-social behaviour in their area.

“Following the attack several witnesses came forward and their testimony at court was of paramount importance.”

Detective Inspector Jim Colclough, whose team led the enquiry, added: “Identifying these lads became crucial and although the CCTV was shocking you cannot underestimate how difficult it was identifying the people responsible from it.

“This was a horrifying attack that happened in the dark, and I am sure the lads who were responsible for this didn’t think we could get anything from the CCTV but the footage proved how vicious this attack was.

“This is what community policing is about, empowering the community to take a stance against the bullies and to ensure their area is a place where people want to live.